Tag: nozzle

If you are new to 3D printing, you might encounter some problems with your prints that can be frustrating and confusing. One of the most common issues is a clogged nozzle, which can affect the quality and accuracy of your prints. In this blog post, I will explain how to diagnose a clogged nozzle and what symptoms to look for on your 3D printed part.

A clogged nozzle is when the filament gets stuck or blocked inside the nozzle, preventing it from extruding properly. This can happen for various reasons, such as using low-quality filament, printing at the wrong temperature, or having dust or debris in the nozzle.

A clogged nozzle can cause several problems with your prints, such as under-extrusion, stringing, blobs, gaps, or layer shifts. These symptoms can ruin your print and waste your time and filament. It is important to diagnose a clogged nozzle as soon as possible and fix it before it gets worse.

The good news is that diagnosing a clogged nozzle is not very difficult. You just need to pay attention to some signs that indicate that something is wrong with your nozzle. Here are some of the most common symptoms of a clogged nozzle:

  • Under-extrusion: This is when the nozzle does not extrude enough filament to fill the gaps between the layers or the perimeters. This results in thin or missing walls, weak infill, or holes in the print.
  • Stringing: This is when the nozzle oozes filament during travel moves, creating thin strings or hairs between different parts of the print. This can make your print look messy and require post-processing to remove them.
  • Blobs: This is when the nozzle extrudes too much filament at certain points, creating bumps or lumps on the surface of the print. This can affect the smoothness and accuracy of your print and make it look unprofessional.
  • Gaps: This is when the nozzle skips or misses some parts of the print, leaving empty spaces or holes in the model. This can compromise the integrity and functionality of your print and make it look incomplete.
  • Layer shifts: This is when the nozzle moves out of alignment during printing, causing the layers to shift or misalign. This can distort the shape and dimensions of your print and make it unusable.

If you notice any of these symptoms on your 3D printed part, check your nozzle for clogging and either fix or replace the nozzle.

A clogged nozzle is one of the most common problems that can affect your 3D printer. It can cause poor print quality, filament jams, and even damage your printer. I talk a lot about how to fix something after something has gone wrong, but I realized that it would be much better to explain how to avoid having a problem in the first place.

The first step is to choose the right filament for your printer. Different filaments have different melting temperatures, flow rates, and properties. Some filaments, such as ABS, PLA, and PETG, are easy to print with and have low chances of clogging. Other filaments, such as wood, metal, or glow-in-the-dark, have additives that can increase the risk of clogging. If you want to use these filaments, make sure you have a nozzle that can handle them, such as a hardened steel or ruby nozzle.

The second step is to clean your nozzle regularly. You can use a needle or a wire to poke through the nozzle hole and remove any debris or filament residue. You can also use a cold pull technique, which involves heating up the nozzle, inserting a piece of filament, letting it cool down slightly, and then pulling it out with a quick motion. This can help remove any material that is stuck inside the nozzle.

The third step is to calibrate your printer settings. You should check your extrusion multiplier, retraction distance, retraction speed, and temperature settings. These settings affect how much filament is pushed through the nozzle and how fast it cools down. If these settings are too high or too low, they can cause over-extrusion or under-extrusion, which can lead to clogging. You can use a calibration cube or a test print to fine-tune your settings and achieve optimal results.

I’ve seen a number of help requests lately that have to do with clogged nozzles. I’ll share how I go about unclogging nozzles, but I will also share how I deal with clogged nozzles afterwards.

To unclog a nozzle, the first thing I do is heat up the hotend as high as the software will allow. This can help break down any clogs that may be in the nozzle into smaller pieces and allow them to pass through. Next, I’ll take a small pin or needle and carefully push it into the nozzle and try to remove any material that I find there.

If that is not successful, the next thing I will try is a cold pull. Heat the nozzle up and then let it cool down completely. The idea is that (hopefully) any impurities will be absorbed into the filament so that we can pull it out when it solidifies. Next, I typically remove the bowden tube connection so that I can pull on the filament directly. Heat up the hot end and start pulling gently, but firmly on the filament. You will feel it start to give at a certain temperature. Pull it all the way out and cut the tip off. This should remove some of the impurities that were previously stuck in the nozzle. Do this 2-3 more times.

If you are not successful with either of these methods, I just replace the entire hot end. For most hobby printers, hot ends cost $10 – $20. I usually keep a spare on hand and just swap it out.

Changing your printer Nozzle

Sometimes you need to change your nozzle. I do this most frequently when I change filament materials or when I need more details. I made a jewelry box for my wife last year and I used a wood PLA filament. Most hobby printers (including mine) use a default 0.4mm nozzle tip. The wood clogged my tip, so I switched it out to a larger tip. Other times, I want to print figurines for my kids with a lot of details so I want to switch to a smaller tip.

Here is what I do:

  • Heat up the extruder. I’ve found that the hot end material contracts around the nozzle tip. Heating it up expands the hot end and makes the nozzle easier to remove.
  • Remove the old tip
  • Insert the new tip
  • Adjust the nozzle size and line width in Cura (or other preferred slicer)
  • Calibrate e-steps to compensate for new flow rate
  • PID tune to adjust heating properties
  • Level bed